DE1112693B - Process for the production of water vapor and grease proof, wet strength packaging material with vegetable parchment paper coated on one side with plastic as a component - Google Patents

Description

The invention relates to a method for the production of water vapor and grease proof, wet strength Packaging material with vegetable parchment paper coated on one side with plastic as Component.

Vegetable parchment paper has been widely used as a packaging material for decades Used for purposes where the impermeability of grease is important, for example for the packaging of Dietary fats. For the latter purpose it is particularly well suited because of a number of excellent ones Properties. It is grease-proof, especially in the long term, wet-strength, completely odorless and tasteless and physiologically harmless.

However, vegetable parchment paper lacks one property that makes it an ideal packaging material for water-containing food fats such as margarine, butter and the like. To make, namely the Water vapor tightness. For the packaging of z. B. margarine and butter but plays the water vapor tightness insofar as the undesired "edging out" of these fats is a consequence the water loss on the surface is only prevented by a well water vapor-tight packaging material can be.

It has therefore already been used for this purpose as a wrapper, z. B. aluminum foil, which is laminated with vegetable parchment paper. If you use aluminum foil as a component, then their sensitivity to kinking becomes annoyingly noticeable during packaging. the Pores and fine hairline cracks that occur when it is bent or folded reduce the impermeability to water vapor not insignificant.

The lamination of a vegetable parchment paper with a plastic film is also described been. But since the plastic film with the parchment paper is only flawless with a hoof Adhesive intermediate layer can connect, the application of such is necessary before lamination.

A deficiency of all composite packaging materials, which start from parchment paper that has already been parchmented, is that the weight per square meter of the usable packaging means is relatively high. Efforts are made to reduce the weight per square meter by using plastic films that are as thin as possible; However, there are limits to this due to the required values for water vapor tightness, which must not be fallen below. A reduction in the weight per square meter of the sheet combined with the film. Vegetable methods of manufacture
of water vapor and grease proof,

wet strength packaging material

with vegetable parchment paper coated on one side with plastic

as a component

Applicant:

Heinrich Nicolaus G. mb H.,
Kempten (Allgäu)

Werner Schoppmeyer, Munich,
and Dipl.-Ing. Horst-Georg Schmidt,

Kempten {Allgäu),
have been named as inventors

Parchment paper below a minimum value also encounters difficulties because such Do not allow thin sheets of parchment base paper to run smoothly over the parchment machine, as they Tear easily when wet and also turn over after passing through the parchment bath the nip rollers can loop.

It has already been proposed to use vegetable parchment paper with a line of plastic dispersions to provide. With this method, however, the Solvents or dispersants can be removed by heat treatment.

It is also known to produce leather substitute by having an absorbent paper with a Treated plastic solution, which penetrates into the fiber, and this material after Evaporation of the solvent is then parchment. With this known method it results and to a greater extent when using thin paper webs that the solution through the paper passes through, so that there is no uniform parchment and no closed surface on the other hand arises. For the production of a packaging material using a This method is not suitable for thin parchment base paper.

1Q9 677/181

It has now been found that packaging material without the above-mentioned deficiencies is the simplest Way can be produced by placing on the surface of a thin sheet of parchment base paper, preferably one with a weight of about 20 to 30 g / m², without deeper penetration a thin layer of water vapor-tight and acid-resistant plastic, e.g. B. polyethylene, in softened or in the molten state, for example by extrusion, applies both layers by simple heat and pressure treatment connects to one another in a known manner and then this Material in a known manner on a normal parchment machine z. B. with sulfuric acid parchmented. The parchment is done at the same speed as the parchment from the usual thicker parchment base paper webs. The plastic layer is covered by the parchment, for example about 70% sulfuric acid, not attacked. The usual washing out of the parchmentic acid and the subsequent neutralization and drying on the drying section of the parchment machine take place without any difficulty.

Other plastics suitable for the purpose according to the invention include polypropylene, Polyvinyl chloride, polyvinylidene chloride, polyamide, polystyrene and polycarbonate in question.

example

A parchment base paper web of about 24 g / m² is made in a known manner on an extruder system by means of a polyethylene film of about 20 μ connected. This composite material is subsequently Parchmented in the usual way with 70% sulfuric acid, washed out and dried.

The material produced by combining plastic with parchment base paper is made with at normal speed through the parchment machine. Also the usual washing out of the Parchment acid as well as the subsequent neutralization and drying on the dryer section of the Machine can be done without any difficulty.

According to the invention gives a packaging material consisting of a layer of vegetabilischem parchment paper very thin, as was previously not technically producible, and a plastic layer, which has the known good properties of vegetable parchment paper and beyond due of its related plastic layer yet is distinguished by water vapor tightness. The plastic layer also gives it increased wet strength. If suitable thermoplastics are used, their sealability can be used to advantage for the production of particularly tight packs. This material coated on one side with plastic can advantageously also be used as a heat-sealing lamination layer for connecting to other material webs, e.g. B. with paper

ίο or especially aluminum foils. This method is particularly economical.

Because in the process according to the invention there is no solvent in an intermediate treatment need to be evaporated and also the union of paper and plastic without the aid an adhesive intermediate layer is carried out, the process means in this regard as well the resulting simplification and time savings represent a remarkable technical advance.

By using suitable plastics, a packaging material that is also largely aroma-proof is obtained.

Claims (5)

PATENT CLAIMS: 1. A process for the production of water vapor- and grease-proof, wet-strength packaging material with vegetable parchment paper coated on one side with plastic as a component, characterized in that a plastic layer is applied on one side in a softened or melted state on a web of thin parchment base paper and then the combination in on is known to be parchment. 2. The method according to claim 1, characterized in that the parchment base paper has a weight of 20 to 30 g / m ² . 3. The method according to claim 1 and 2, characterized in that the plastic layer is extruded on will. 4. The method according to claim 1 to 3, characterized in that the plastic layer consists of Made of polyethylene. 5. The method according to claim 1 to 4, characterized in that according to claims 1 to 4 material produced by heat sealing with other material webs, in particular with Aluminum foil connects. Considered publications:
British Patent Nos. 407 246, 787 482.